Researchers show that slow-moving earthquakes are controlled by rock permeability

Earthquakes are the most dramatic and noteworthy results of tectonic plate movement. They are often destructive and deadly, or at the very least physically felt—they're literally groundbreaking geological events. However not all tectonic movement results in effects that humans can perceive.

Slow slip events occur when pent up tectonic forces are released over the course of a few days or months, like an earthquake unfolding in slow motion. The more gradual movement means people won't feel the earth shaking beneath their feet and buildings won't collapse. But the lack of destruction does not make slow slip events less scientifically important. In fact, their role in the earthquake cycle may help lead to a better model to predict when earthquakes happen.

In a paper published recently in Geophysical Research Letters, a Jackson School of Geosciences research group explores how the makeup of rocks, specifically their permeability—or how easily fluids can flow through them—affects the frequency and intensity of slow slip events.

Their tests showed how pores in the rocks could control the regular slow slip events at this subduction zone. Previous studies have suggested that a layer of impermeable rock at the top of the descending tectonic plate serves as a sealed lid, trapping fluid in the pores of underlying rock layers.

As fluid accumulates beneath the seal, the pressure builds, eventually becoming high enough to trigger a slow slip event or earthquake. This event then breaks the impermeable seal, temporarily fracturing the rocks, allowing them to soak up fluids. Within a few months, the rocks heal and return to their initial permeability, and the cycle starts all over again.

In this work,  for the first time, the researchers showed that using rocks that are representative of those at depth, that permeability is controlling slow slip events.

Nicola Tisato et al, Permeability and Elastic Properties of Rocks From the Northern Hikurangi Margin: Implications for Slow‐Slip Events, Geophysical Research Letters (2024). DOI: 10.1029/2023GL103696

What are nanoplastics? Concern is growing about particles too small to see

It's become common to read/hear that microplastics—little bits of plastic, smaller than a pencil eraser—are turning up everywhere and in everything, including the ocean, farmland, food and human bodies. Now a new term is gaining attention: nanoplastics. These particles are even tinier than microplastics—so small that they're invisible to the naked eye.

Nanoplastics are a type of microplastic, distinguished by their extremely small size. Microplastics are usually less than 5 millimeters across; nanoplastics are between 1 and 1,000 nanometers across. For comparison, an average human hair is roughly 80,000–100,000 nanometers wide.

Nanoplastics are attracting growing concern thanks to recent technological advances that have made researchers more able to detect and analyze them. Their smaller size means that they are more easily transported over long distances and into more diverse environments than microplastics. They can more easily penetrate cells and tissues in living organisms, which could lead to different and more acute toxicological effects.

Studies in the past two years have found nanoplastics in human blood, in liver and lung cells, and in reproductive tissues such as the placenta and the testes. Around the world, nanoplastics have been found in the air, in seawater, in snow and in soil.
We already know that microplastics are present from the heights of Mount Everest to deep ocean trenches. Now there is growing evidence that nanoplastics are more prevalent than larger microplastics in the environment.

Computer models suggest modern plate tectonics are due to blobs left behind by cosmic collision

A small team of geologists and seismologists  has found evidence via computer modeling that suggest giant blobs of material near the Earth's core, believed to have been created by a cosmic collision 4.5 billion years ago, may be responsible for modern plate tectonics.

In their study, published in the journal Geophysical Research Letters, the group used existing data on the blobs, known more technically as large, low-velocity provinces (LLVPs), and used it to create computer simulations and models showing their impact on the Earth over long time scales.

In the 1980s, geophysicists discovered what they described as giant blobs of unknown material near Earth's center—one below the Pacific Ocean, the other below parts of Africa. Then, last year,  another team found evidence that the blobs (LLVPs) are remnants of Theia, a planet that struck the Earth 4.5 billion years ago. The rest of the debris from the collision, theory suggests, coalesced in Earth's orbit, forming the moon.

For this new study, the team  used computer models to show what sort of impact the LLVPs may have had on the Earth's crust over the past millions of years, and report evidence that they may be responsible for modern plate tectonics.

Data for the models came from seismic readings that have shown the LLVPs are made up of different material than either the core or mantle. After some tweaking, the models showed that approximately 200 million years after Theia struck the Earth, pressure from the LLVPs led to the creation of hot plumes stretching from near the core to the surface. That caused some sections of the surface to sink, which led to subduction.

Subduction eventually led to the breaks in the surface that today serve as borders for tectonic plates. The researchers suggest their models may explain why some of the oldest minerals on Earth show evidence of subduction.

Qian Yuan et al, A Giant Impact Origin for the First Subduction on Earth, Geophysical Research Letters (2024). DOI: 10.1029/2023GL106723

Study shows that astrocytes integrate information about past events in their soma

Neurons are known to communicate and integrate information they receive from their dendrites, branch-like structures extending from their body. In contrast, the activity in astrocytes, a class of star-shaped glial cells found in the central nervous system (CNS), has so far been assumed to be largely uncoordinated, thus lacking the central integration of information.

Researchers at University of Zurich and ETH Zurich recently gathered evidence suggesting that this widespread description of astrocytes might be false or at least incomplete, as they do in fact integrate information about past events.

Their findings, published in Nature Neuroscience, specifically reveal the conditional integration of calcium signals in processes taking place in the astrocytes' soma (i.e., cell body).

Peter Rupprecht et al, Centripetal integration of past events in hippocampal astrocytes regulated by locus coeruleus, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01612-8

Researchers estimate vaccines have saved 154 million lives over past half-century

An international team of health and medical researchers including workers at the WHO, working with economists and modeling specialists, has found that the use of vaccines to prevent or treat disease has saved the lives of approximately 154 million people over the past half-century.

In their study, published in The Lancet, the group used mathematical and statistical modeling to develop estimates for lives saved due to vaccines and then added them together to find the total. The goal of the team was to evaluate the degree of success of the Expanded Program on Immunization (EPI) launched by the World Health Organization in 1974. The goal of the EPI has been to vaccinate all the children in the world against the most common deadly diseases. At its onset, the list included seven diseases; it has since been expanded to include 14. As part of that effort, research has been conducted to develop vaccines, test them and then to use them once they have been declared both safe and effective. Since its inception, the EPI program has led to the development of many vaccines and the vaccination of millions of people, preventing suffering and death. In this new effort, the research team sought to find out how successful the program has been. The work involved collecting and analyzing data at the local, regional and global levels. As part of that effort, they created 22 models based on 50 years of vaccination data for people around the world. The team then used the models to estimate lives saved and found the total to be approximately 154 million since 1974. The research team also found that children benefited the most from vaccination—101 million of the lives saved were under the age of 1. They also found evidence that vaccination programs had a major impact on infant mortality rates—over the past half-century, rates have declined globally by 40%. The researchers also found that the measles vaccine made the biggest impact—it was responsible for 60% of the lives saved.

 Andrew J Shattock et al, Contribution of vaccination to improved survival and health: modelling 50 years of the Expanded Programme on Immunization, The Lancet (2024). DOI: 10.1016/S0140-6736(24)00850-X

Scientists pinpoint new vaccine adjuvant that promotes potent anti-tumor immunity

Scientists  have made an important breakthrough that offers promise for developing new immune therapies for cancer. They have discovered that a vaccine adjuvant called C100 promotes potent anti-tumor immunity when it is injected directly into tumors in an animal model.

The scientists found that C100, derived from chitin—one of the most common building materials in nature, and which gives strength to the exoskeletons of crustaceans, insects, and the cell walls of fungi—is highly effective at stimulating a key sensing and signaling molecule which regulates anti-tumor immune responses.

Their work has been published in Cell Reports Medicine.

The scientists now know how C100 exclusively activates one arm of a specific signaling pathway (cGAS-STING) without causing inflammatory responses that could interfere with anti-tumor immunity and which may otherwise prevent therapies from achieving clinical success.

Additionally, the research team discovered that injecting C100 led to synergistic therapeutic effects with a "checkpoint blocker," which can release the brakes on the immune response.

 Intratumoural delivery of the chitin-derived C100 adjuvant promotes robust STING, IFNAR and CD8+ T cell dependant anti-tumour immunity, Cell Reports Medicine (2024). DOI: 10.1016/j.xcrm.2024.101560. www.cell.com/cell-reports-medi … 2666-3791(24)00252-0

How to illuminate the ‘ugly’ side of science
Data repositories, workshops and alternative journals allow scientists to share and discuss negative results, which could help to solve the reproducibility crisis and give machine learning a boost. Publishing negative-result studies is often seen as not worth the time and effort, yet “understanding the reasons for null results can really test and expand our theoretical understanding”, says psychologist Wendy Ross. And highlighting negative results can help students to see that “you are not a bad researcher because you fail”, adds computer scientist Ella Peltonen.

https://www.nature.com/articles/d41586-024-01389-7?utm_source=Live+...

Elephants use gestures and vocal cues when greeting each other, study reports

A team of animal behaviourists has found that elephants use gestures and vocal cues when they greet one another.

In their study, published in the journal Communications Biology, the group observed a month's worth of greetings between African elephants living in the Jafuta Reserve in Zimbabwe in 2021.

Prior research has shown that elephants are highly intelligent, ranking close to dolphins. They also have complex matriarchal social structures. For this new study, the research team wondered if elephants have ways to communicate with one another that had not been observed during prior research efforts. They embarked on an observational study focused on elephant greetings.
The researchers ventured into the field at the reserve in Zimbabwe and watched and recorded encounters between elephants for one month in 2021. They observed 1,014 physical actions taken by elephants engaged in a greeting and 268 vocalizations.

The researchers found that elephants place importance on greeting one another. When two elephants who have not seen each other for a while meet, they both engage in apparently meaningful behavior. Gestures included swinging the trunk or using it to touch, ear-flapping and ear-spreading. Vocalizations tended to be rumbles of different sorts.

Part 1

The research team noted that rumblings and gestures were often combined. Behaviors during greetings also sometimes involved urination, defecation and secreting sweat in the temporal gland, which emits odors into the air.

The researchers also found that the type of behaviors differed depending on whether the two elephants were looking at one another—most were more likely to engage in gestures when they knew the other elephant was looking at them. To get the attention of elephants who hadn't noticed them, they were also seen to engage in ear-flapping, which generates a lot of noise.

The research team concludes that the gestures and vocalizations used by the elephants appear to be part of a complicated system of communication used by the elephants to convey information during encounters.

Vesta Eleuteri et al, Multimodal communication and audience directedness in the greeting behaviour of semi-captive African savannah elephants, Communications Biology (2024). DOI: 10.1038/s42003-024-06133-5

Part 2

AI systems are already skilled at deceiving and manipulating humans, study shows

Many artificial intelligence (AI) systems have already learned how to deceive humans, even systems that have been trained to be helpful and honest. In a review article published in the journal Patterns on May 10, researchers describe the risks of deception by AI systems and call for governments to develop strong regulations to address this issue as soon as possible.

AI developers do not have a confident understanding of what causes undesirable AI behaviors like deception. But generally speaking, researchers think AI deception arises because a deception-based strategy turned out to be the best way to perform well at the given AI's training task. Deception helps them achieve their goals.

The most striking example of AI deception the researchers uncovered in their analysis was Meta's CICERO, an AI system designed to play the game Diplomacy, which is a world-conquest game that involves building alliances. Even though Meta claims it trained CICERO to be "largely honest and helpful" and to "never intentionally backstab" its human allies while playing the game, the data the company published along with its Science paper revealed that CICERO didn't play fair.

They  found that Meta's AI had learned to be a master of deception.

Other AI systems demonstrated the ability to bluff in a game of Texas hold 'em poker against professional human players, to fake attacks during the strategy game Starcraft II in order to defeat opponents, and to misrepresent their preferences in order to gain the upper hand in economic negotiations.

While it may seem harmless if AI systems cheat at games, it can lead to "breakthroughs in deceptive AI capabilities" that can spiral into more advanced forms of AI deception in the future.

Some AI systems have even learned to cheat tests designed to evaluate their safety, the researchers found. In one study, AI organisms in a digital simulator "played dead" in order to trick a test built to eliminate AI systems that rapidly replicate.

By systematically cheating the safety tests imposed on it by human developers and regulators, a deceptive AI can lead us humans into a false sense of security.

The major near-term risks of deceptive AI include making it easier for hostile actors to commit fraud and tamper with elections, warn experts. Eventually, if these systems can refine this unsettling skill set, humans could lose control of them.

As the deceptive capabilities of AI systems become more advanced, the dangers they pose to society will become increasingly serious.

AI deception: A survey of examples, risks, and potential solutions, Patterns (2024). DOI: 10.1016/j.patter.2024.100988

Sky-high vanity: Constructing the world's tallest buildings creates high emissions, researchers say

Since ancient times, people have built structures that reach for the skies—from the steep spires of medieval towers to the grand domes of ancient cathedrals and mosques. Today the quest is to build the world's tallest skyscrapers, such as Burj Khalifa in Dubai. Soaring above the rest, its decorative spire accounts for 29% of its total height—4,000 tons of structural steel just for aesthetics.

Burj Khalifa isn't unique in this respect. "Vanity height"—the extra height from a skyscraper's highest occupied floor to its architectural top—shapes city skylines around the globe.
In a world where environmental concerns are paramount, is such architectural vanity justifiable?
Research shows the pursuit of "vanity height" makes this a pressing issue. Even a modest spire increases the carbon emissions from the production of materials for a skyscraper's structure by about 15%.

The hidden cost of vanity height
Sixty years ago, the renowned Bangladeshi-American architect and engineer Fazlur Rahman Khan demonstrated the exponential impact of a building's height on the amount of material needed to build it. Indeed, doubling the height of a building could triple the structural materials required. A stronger structure, using more materials, is needed to withstand greater wind and earthquake loads on taller buildings. This means there's a large "embodied carbon premium for height." This premium is the additional greenhouse gas emissions from producing the extra materials needed for a taller skyscraper. A telling example from our study shows that even a modest spire, making up 16% of a building's total height, can increase the embodied carbon of a 90-story skyscraper by 14%. In maximizing the building's height for aesthetic, status or financial reasons, designers are prioritizing these concerns over environmental sustainability.

In light of these findings, researchers call on the council on Tall Buildings and Urban Habitat to remove the incentive for vanity height. They propose the “height to highest occupied floor” be adopted as the main standard for ranking skyscrapers by height.

https://www.sciencedirect.com/science/article/pii/S0959652624017827...

https://theconversation.com/sky-high-vanity-constructing-the-worlds...

GoT-ChA: New tool reveals how gene mutations affect cells

A team co-led by researchers at Weill Cornell Medicine and the New York Genome Center has developed an advanced method for revealing how gene mutations disrupt the normal packaging of DNA. These structural changes, which alter patterns of gene activity in a cell, are known as epigenetic changes and can lead to malignancy.

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Why evolution often favors small animals and other organisms

Small really does seem to be beautiful in evolutionary terms. The largest dinosaurs, pterosaurs and mammals may look impressive but these giants are vastly outnumbered by microscopic bacteria and single-celled algae and fungi. Small organisms are also ancient and incredibly resilient.

How Far Can Plastic  Reach Into Your Lungs?

Miniscule fragments of plastic pollution invade the human body every day without our knowing it, not just from eating and drinking but from simply breathing.
By some estimates, the average person inhales a credit card's worth of plastic every week with unknown health effects. In 2022, scientists found microplastics hiding in the deepest parts of the human lung for the first time.
The worldwide spread of plastic has not only crept up on us, it has crept up in us, and scientists are now rushing to figure out where these pollutants go when we breathe them in, how long they stick around for, and if they have toxic effects.

Researchers at the University of Technology Sydney (UTS) have now tracked the passage of plastic as it flows through the respiratory system. Their model builds on a pioneering attempt in 2023 to identify hotspots where microplastics and nanoplastics might gather in our airways.

That prior study focused mostly on modeling the upper airway tract, but the new study considers how air and particles flow through the entire tract, "from the nasal cavity down to the 13th generation of the bronchial tree".

It also models three different breathing rates – slow, medium, and fast – and three different sizes of plastic fragments; large microplastics, microplastics, and nanoplastics.

The result is a delicate balance, the researchers say, between the way that gravity drags plastics onto a surface and the way that wind blows them along a passageway.
At a normal breathing rate, the model suggests microplastics in the air can come to cover half the surface area of a nasal cavity. At slower breathing rates, medium-sized pollutants were largely deposited in the upper airway, including the nasal cavity, the voice box, and the junction where the windpipe connects to the throat. Meanwhile, smaller, dust-like particles were distributed more evenly throughout the upper and lower respiratory tract.
Larger microplastics displayed a tendency for rapid deposition in the upper airways, whereas smaller nanoplastics exhibited a higher likelihood of escape or reaching deeper airway generations," the researchers conclude.

https://www.sciencedirect.com/science/article/pii/S2666765724000437...

Part 1

Their findings support previous studies that led scientists to suspect that the smaller the plastic fragment, the more likely it is to penetrate deeper into the lung, possibly infiltrating the alveolar sacs where crucial gas exchange occurs.

It's not just degraded plastic products, like drink bottles, that are causing this threat, either. Common cosmetic products, like gritty toothpaste, are made purposefully with these tiny fragments. Some reports estimate that in India, toothpaste is responsible for emitting 1.4 billion grams of microplastic particles each year.

When breathed in, experimental evidence strongly suggests that such tiny plastics have the capacity to trigger inflammation, oxidative stress, lung tissue damage, or systemic dysfunction in the respiratory tract. So far, however, research on the potential health outcomes of microplastics is mostly confined to animal models and human cells.
One recent exception was a study among surgery patients, which found that those who had more plastic in a main artery of their body had a higher chance of heart attack, stroke, or death in the following years. Given the ramifications, associations between cardiac health and plastic pollutants needs to be further explored.

"Plastic particle air pollution is now pervasive and inhalation ranks as the second most likely pathway for human exposure.
For the health of humans everywhere, it is crucial that toxicologists fully understand where these ubiquitous particles are going when we breathe them in and what they are doing to our bodies.
Part 2

Some Snakes Fake Their Own Deaths, And They Even Use Special Effects!

Playing dead is a common defense strategy in the animal kingdom, but some especially melodramatic snakes have now been seen dialing it up to 11. In addition to flopping inert, mouths agape, dice snakes (Natrix tessellata) add some amazingly gross special effects. They'll defecate and smear themselves in feces, excrete stinky musk, and even start bleeding from the mouth, for what might be the most realistic deaths ever feigned in nature.

Scientists studying these top-tier acting skills found that adding a little something more allows the snake to escape more quickly, evading predation more adroitly than snakes that don't go the extra mile.

A behaviour known as apparent death – or tonic immobility – is actually quite common in nature, across a wide range of taxa. Its ubiquity suggests that it's an effective defense against predators, although exactly why is unclear. Some research suggests that it's often a last-ditch effort to escape after predator-prey contact has already occurred.

it works, some snakes seem to have found a way to tip the odds even further in their favor. Eastern hog-nosed snakes (Heterodon platirhinos), for example, flip onto their backs, convulse, puke, and excrete musk. This is a foul-smelling substance produced in glands near the snake's cloaca, like the anal glands of skunks.

Dice snakes – a non-venomous species that mainly eats fish – are known to have feces and musk among in their defensive toolkit; when alarmed, they struggle, hiss, and coat themselves in stench. They also play dead, and have been seen bleeding from the mouth using an ability known as autohemorrhaging.

These snakes are considered as tasty  to quite a number of predators, including reptiles, birds, and mammals.

https://royalsocietypublishing.org/doi/10.1098/rsbl.2024.0058

Evidence of a travel direction signal that is independent from head direction in humans

We generally assume that when humans are walking or otherwise moving in space, their head faces towards the direction they are traveling in. Nonetheless, travel direction and head direction are distinct factors associated with the processing of different types of spatial information.

Researchers recently unveiled a travel direction-related signal represented in the human mind that appears to be independent from head direction. Their paper, published in the Journal of Experimental Psychology: General, could soon open new avenues for neuroscience and psychology research focusing on spatial navigation.

Finding your way can be complicated, but in some ways keeping track of your position requires a few basic pieces of information—your speed, how long you have been going, what direction you are going in. 

Head direction and travel direction have been found to provide very different information. Overall, travel direction plays a greater role than head direction in shaping the trajectory that humans or animals will follow while moving in their surrounding environment.

Moreover, studies found that people's heads are not always facing the direction they are going in.

Researchers carried out a behavioral experiment aimed at searching for a travel direction signal that is entirely separate from head direction.

This recent study ( and its results) was the first to hint at the existence of a signal of travel direction in humans that is independent from head direction. The findings it gathered prompt interesting new questions about the unique contributions of travel direction to spatial navigation.

 You Cheng et al, (Don't) look where you are going: Evidence for a travel direction signal in humans that is independent of head direction., Journal of Experimental Psychology: General (2024). DOI: 10.1037/xge0001538.

 Augmented Reality Contact Lens!

Mojo Lens, an in-development contact lens with an embedded augmented reality display and the electronics needed to run it wirelessly. With a tethered prototype held up to our eye, we could clearly see how the .5mm wide microLED shows images and text as well as a user interface that can be controlled with literal eye tracking. Here's how the Mojo system works and exactly what hardware is packed inside this smart contact lens!

Bid to end deadly cooking methods which stoke global warming

Fifty countries are meeting in France  today to discuss the lack of access to clean cooking methods worldwide which causes millions of deaths every year and fuels global warming.

Some 2.3 billion people across 128 countries breathe in harmful smoke when they cook on basic stoves or over open fires, according to an International Energy Agency (IEA)-African Development Bank (ADB) report that sounded the alarm last year.

It said 3.7 million people a year die prematurely from harmful cooking practices, with children and women most at risk.

The IEA said the "unprecedented" Paris gathering aims to be "a moment of changing the direction". The problem "touches on gender, it touches on forestry, it touches on climate change, it touches on energy, it touches on health.

A third of the world cooks with fuels which produce harmful fumes when burned, including wood, charcoal, coal, animal dung and agricultural waste.

They pollute indoor and outdoor air with fine particles that penetrate the lungs and cause multiple respiratory and cardiovascular problems, including cancer and strokes.

These cooking practices are the third highest cause of premature deaths in the world and the second highest in Africa. In young children , they are a major cause of pneumonia, experts say.

They also prevent women and children from accessing education or earning a wage, as they spend hours looking for fuel.

Part 1

Greenhouse gas emissions from using basic stoves and deforestation from collecting wood also contribute hugely to global warming.

Switching to clean cooking methods, such as LPG or electric cooking, would save 1.5 billion tonnes of CO₂ a year by 2030—roughly the amount emitted by ships and planes last year, according to the IEA.

IEA also recommends strong national leadership as well as grassroots efforts to change social norms.

Source: AFP and other news agencies

This New Plastic Disappears When You Don't Need It Anymore

The plastic that eats itself

Our reliance on plastic has become a huge problem, which is why researchers are excited about a new type of material – one that comes with built-in biodegrading capabilities, due to the bacterial spores living inside it. The new self-digesting plastic combines thermoplastic polyurethane (TPU) and Bacillus subtilis bacteria, which had to be engineered to survive the high temperatures involved in plastic production. By repeatedly exposing the spores to increasing levels of heat, the team of researchers behind this new work found that the bacteria could eventually cope with the temperatures of 135 degrees Celsius (275 degrees Fahrenheit) required to mix the bacterial spores and TPU together. Past efforts to find ways to degrade plastics, fast, have often sourced bacterial enzymes and fungi from soils and compost heaps where those microbes are naturally abundant. But this new material needs only the bacterial spores inside it, reawakened with some nutrients and moisture, to start breaking down.

https://www.nature.com/articles/s41467-024-47132-8

A minimal cognitive architecture reproduces control of human decision-making processes

Neuroscientists and psychologists have been trying to pinpoint the processes behind human decision-making for decades. While their efforts led to numerous interesting insights, the intricacies of complex decision-making remain poorly understood.

Researchers at the Paris Brain Institute carried out a study aimed at better understanding how the human brain allocates its resources when making decisions. Their paper, published in Communications Psychology, introduces an architecture that operates the online metacognitive control of decisions (oMCD), a theoretical construct describing why and how the brain choses to stop of continue deliberating.

Past studies have found that humans do not always invest their maximum mental efforts when making decisions. This can lead to various widely documented errors and cognitive biases (i.e., recurring deviations from rational thinking).

So when making a decision, what determines the amount of mental effort we invest in decisions?

Previous behavioral research suggested that, for certain kinds of decisions (so-called 'evidence-based' decisions), this may be done by balancing decision confidence (which tends to increase with mental effort) with the cost of mental effort. This then triggered the question: can this work for all kinds of decisions?

To address this question, researchers should first demonstrate that a confidence-based control policy eventually yields mental effort investments resembling those of optimal control policies that are specific to different kinds of decisions. This was one of the primary objectives of this work.

Part 1

Researchers approached this problem in many different ways.

In the context of this study, the researchers effectively provided two lines of evidence. The first one is theoretical in essence. Specifically, we rely on so-called Markov Decision Processes (MDPs) to demonstrate that confidence-based control policies are quasi-optimal for a broad class of decisions."

After having identified the non-trivial quantitative properties of confidence-based control policies, the researchers set out to determine whether these properties can be found in empirical data gathered in experiments where humans completed decision-making tasks. The properties they specifically sought for included three-way interactions between the values of different options, decision times and the reported confidence in a decision.

In brief, they identified a minimal cognitive architecture for quasi-optimal decision control (in terms of how much effort is invested). Importantly, this architecture may generalize over most, if not all, kinds of decision types. This implies that a single brain system may operate decision control, irrespective of the type of decision.

 Juliette Bénon et al, The online metacognitive control of decisions, Communications Psychology (2024). DOI: 10.1038/s44271-024-00071-y.

Part 2

 Why subsequent bouts of dengue are worse than a first-time infection

A massive upsurge in dengue cases marked by multiple outbreaks is occurring worldwide and raising new questions about who is at elevated risk of severe forms of the mosquito-transmitted disease.

Incidence of the infection has increased by orders of magnitude throughout the so-called dengue belt, which encompasses Central and South America, Sub-Saharan Africa, Southeast Asia and swaths of the South Pacific, home to densely populated islands. Dengue, without question, is the most widespread and rapidly increasing vector-borne disease in the world, according to the World Health Organization.

The story is similar in other dengue-affected areas of the world where lapses in vector control have conspired with global climate change to create an explosion of bloodthirsty mosquitoes, swarms of them moving into regions once considered dengue-free. Only female mosquitoes feed on blood, they're in constant need of the nutrients in it to nurture their eggs.

Now, more than two decades of dengue surveillance  is answering a slew of questions at a time when the world needs guidance most.

Findings from the research have revealed how various subgroups—what virologists call subtypes—of the dengue virus influence future risk of severe infection. It has been known for years that those who become infected in subsequent outbreaks, after a usually mild bout with a first-time infection, are at significant risk of severe disease in later dengue exposures. New research finally has analyzed more than 15,000 cases to discern why that is so.

Writing in Science Translational Medicine, a global team of scientists has explained how the four dengue viral subtypes—DENV-1, 2, 3, and 4—influence the risk of repeated severe infections. The findings provide a new framework for disease monitoring and lay the foundation for vaccination strategies as the new dengue immunizations emerge.

Part 1

The team also underscored how dengue, a pernicious tropical malady, can be understood within the context of other common viral diseases that circle the globe.

The ability of viruses, such as SARS-CoV- 2 and influenza, to continuously change their genetic structure in response to the selective pressure of population immunity complicates control efforts.

In the case of dengue virus, an arbovirus that infects more than 100 million people each year, the situation is even more complex. Individuals with high dengue virus antibody titers are protected from infection and developing severe disease.

However, individuals with sub-neutralizing antibody titers have been shown to have the highest risk of severe disease, through multiple hypothesized mechanisms including antibody-dependent enhancement.

A dengue infection can be tricky. Some patients who have weathered an infection but get infected in a subsequent outbreak can have more severe symptoms the second time around. Yet, most research on repeat dengue infections has regarded each of the serotypes as no different from the other. An assessment of each serotype's genetic differences was needed to provide a clearer picture of potential risks.

To develop that clearer picture, researchers studied each serotype in more than 15,000 patients' infections as a way to peel away much of the mystery surrounding why first-time dengue illnesses are traditionally milder than subsequent ones.

Part 2

To determine how each of the viral serotypes affects the risk of severe disease, the researchers analyzed viral genetic data. The team also studied cases of patients hospitalized for dengue to determine which viral subtype caused their infections. Researchers gathered data from 21 years of dengue surveillance, ranging from 1994 to 2014, in a children's hospital in Bangkok, encompassing 15,281 individual cases. This allowed them to find repeat cases and each viral subtype in all infections.

Based on the pediatric patients' hospital records, researchers discovered a link between hospitalization and the order in which patients became infected with different dengue-virus serotypes. They were also able to determine which combinations of viral subtypes pointed to mild or severe forms of dengue. For instance, people who became infected with serotypes that were very similar, such as DENV-3 and DENV-4, or very different serotypes as in the case of DENV-1 and DENV-4, tended to have a lower risk of severe disease during the second infection.

Patients who were infected with serotypes that were only moderately different had a higher risk of severe symptoms in subsequent infections. The highest risk group in this category involved patients who had an initial infection with DENV-2 followed by a subsequent infection triggered by DENV-1.

The new research adds clarity to a disease risk that may seem paradoxical to the lay public. For example, most people infected with dengue virus for the first time develop extremely mild signs of the disease or none at all. But for those who do get sick, soaring fever, headache, body aches, nausea and rash are the primary symptoms, and they intensify in severe manifestations of the infection.

For more than a century a severe bout with dengue has been known as breakbone fever because of the intensity of the pain and accompanying muscle spasms.

The virus is carried in the tropics and subtropics by Aedes aegypti and Aedes albopictus mosquitoes, which are endemic in the dengue belt. But while the belt, which runs through latitudes 35-degrees North and 35-degrees South, has traditionally been home to dengue-carrying mosquitoes, the arthropods have been extending their range northward as global climate change intensifies, scientists say.

These findings suggest that immune imprinting helps determine dengue disease risk and provides a pathway to monitor the changing risk profile of populations and to quantifying risk profiles of candidate vaccines.

Lin Wang et al, Antigenic distance between primary and secondary dengue infections correlates with disease risk, Science Translational Medicine (2024). DOI: 10.1126/scitranslmed.adk3259

Part 3

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Artificial intelligence tool detects sex-related differences in brain structure

Artificial intelligence (AI) computer programs that process MRI results show differences in how the brains of men and women are organized at a cellular level, a new study shows. These variations were spotted in white matter, tissue primarily located in the human brain's innermost layer, which fosters communication between regions.

The work appears in Scientific Reports.

Men and women are known to experience multiple sclerosis, autism spectrum disorder, migraines, and other brain issues at different rates and with varying symptoms. A detailed understanding of how biological sex impacts the brain is therefore viewed as a way to improve diagnostic tools and treatments. However, while brain size, shape, and weight have been explored, researchers have only a partial picture of the brain's layout at the cellular level.

The new study used an AI technique called machine learning to analyze thousands of MRI brain scans from 471 men and 560 women. Results revealed that the computer programs could accurately distinguish between biological male and female brains by spotting patterns in structure and complexity that were invisible to the human eye.

The findings were validated by three different AI models designed to identify biological sex using their relative strengths in either zeroing in on small portions of white matter or analyzing relationships across larger regions of the brain.

These findings provide a clearer picture of how a living, human brain is structured, which may in turn offer new insight into how many psychiatric and neurological disorders develop and why they can present differently in men and women.

For the research,  researchers started by feeding AI programs existing data examples of brain scans from healthy men and women and also telling the machine programs the biological sex of each brain scan. Since these models were designed to use complex statistical and mathematical methods to get "smarter" over time as they accumulated more data, they eventually "learned" to distinguish biological sex on their own. Importantly, the programs were restricted from using overall brain size and shape to make their determinations.

According to the results, all of the models correctly identified the sex of subject scans between 92% and 98% of the time. Several features in particular helped the machines make their determinations, including how easily and in what direction water could move through brain tissue.

These results highlight the importance of diversity when studying diseases that arise in the human brain.

Part 1

If, as has been historically the case, men are used as a standard model for various disorders, researchers may miss out on critical insight.

While the AI tools could report differences in brain-cell organization, they could not reveal which sex was more likely to have which features.

According to the researchers, the team next plans to explore the development of sex-related brain structure differences over time to better understand environmental, hormonal, and social factors that could play a role in these  changes.

Deep Learning with Diffusion MRI as in vivo Microscope Reveals Sex-related Differences in Human White Matter Microstructure, Scientific Reports (2024).

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Part 2

Analysis suggests people with more copies of ribosomal DNA have higher risks of developing disease

Ribosomal DNA (rDNA) is present in hundreds of copies in the genome, but has not previously been part of genetic analyses. A new study of 500,000 individuals indicates that people who have more copies of rDNA are more likely to develop inflammation and diseases during their lifetimes.

Standard genetic analysis techniques have not studied areas of the human genome that are repetitive, such as ribosomal DNA (rDNA), a fundamental part of the molecular mechanism which makes proteins in cells.

A new study has discovered that genetic disposition to disease can be found in these previously understudied areas of the genome.

The results, published in Cell Genomics, suggest that wider genome analysis could bring opportunities for preventative diagnostics, novel therapeutics, and greater insight into the mechanism of different human diseases.

In this study, samples from 500,000 individuals in the UK Biobank project were analyzed. Researchers used new whole genome sequencing (WGS) techniques to identify differences in numbers of copies of rDNA in each sample, and compared them with other health metrics and medical records.
The researchers found that the number of copies of rDNA in an individual showed strong statistical association with well-established markers of systemic inflammation—such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII). These statistically significant associations were seen in the genomes of individuals of different ethnicities, suggesting a common indicator for risks of future disease.

Part 1

rDNA copy number was also linked with an individual's kidney function within the sample of individuals of European ancestry. A similar effect was seen in samples from other ancestries, but further research using larger sample sizes will be needed to confirm this connection.

 This research highlights the importance of analyzing the whole genome to better understand the factors impacting on our health. This study is also an example of how having access to large biobanks allows us to make unexpected discoveries, and provides new avenues for harnessing the power of genetics to understand human diseases.

Geneticists have long struggled to fully explain the genetic basis of many common complex traits and diseases. This  work suggests that at least part of this missing heritability resides in difficult to sequence regions of the genome such as those encoding ribosomal copy number variation.

Ribosomal DNA Copy Number Variation Associates with Hematological Profiles and Renal Function in the UK Biobank, Cell Genomics (2024). DOI: 10.1016/j.xgen.2024.100562. www.cell.com/cell-genomics/ful … 2666-979X(24)00128-9

Part 2

Scientists develop sticky pesticide to combat pest insects

Researchers  have engineered a biological barrier that protects plants from diseases and pests. It concerns a sticky substance that is sprayed on leaves, to which pests stick.

The researchers hope that this insect glue will help to reduce the use of toxic chemical pesticides. They published their findings in the Proceedings of the National Academy of Sciences.

In the search for alternatives, scientists  turned to nature for inspiration. The carnivorous sundew plant has so-called glandular hairs that secrete a sticky substance to catch insects. The researchers wanted to mimic this to protect the plants and crops in a natural way.

The researchers succeeded in their endeavor.

They transformed vegetable rice oil into a yellow, sticky substance by blowing air over it and grinding it into small particles using a laboratory blender. This results in beads of about one millimeter in diameter that are as sticky as duct tape. The size matches one of the common pest insect: thrips. By catching these insects, plants stay healthier and are less likely to become infected with fungi that the thrips carry with them.

So far, the researchers mainly focused on this type of pest, but the insect glue may also work against other pests, such as the Suzuki fruit fly that currently threatens cherry cultivation. At the same time, the drops are small enough that beneficial insects, such as pollinators, do not get stuck.

Unlike chemical pesticides, insects are unlikely to develop resistance against this adhesive, the researchers think. 

Insects have already evolved so that they avoid adhesion, for example through hairs on their body and a bumpy surface. Increasing their body size remains one of the few escape methods from this sticky trap. That is not nearly as easy as developing tolerance to a chemical substance. If it happens at all, it takes many generations and only happens if the insect glue is used on a large scale.

After application, the sticky substance remains on the leaves for three months and cannot be washed off by rain. That is long enough to control pests until harvest. By spraying the insect glue on crops before the fruits develop, farmers minimize the chance of the pesticide getting onto the food. However, contact with food cannot be ruled out.

The advantage of this pesticide over chemical pesticides is that you can see the small, yellow drops. You can wash it off with water and dish soap. If you do ingest some of it, it is probably not harmful. As it is derived from vegetable oil.

 But scientists still need to investigate how (un)healthy it is exactly.

Ralph van Zwieten et al, Mimicking natural deterrent strategies in plants using adhesive spheres, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2321565121

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Scientists discover blood proteins that may give cancer warning seven years before diagnosis

Two studies  have discovered proteins in the blood that could warn people of cancer more than seven years before it is diagnosed.

Scientists identified 618 proteins linked to 19 different types of cancer, including 107 proteins in a group of people who blood was collected at least seven years before diagnosis. The team has discovered that these proteins could be involved at the very earliest stages of cancer, where it could be prevented.

They think that some of these proteins could be used to detect cancer much earlier than is currently possible. In the future, this could help treat the disease at a much earlier stage or prevent it altogether.

The papers, titled "Identifying proteomic risk factors for cancer using prospective and exome analyses of 1,463 circulating proteins and risk of 19 cancers in the UK Biobank" and "Identifying therapeutic targets for cancer among 2,074 circulating proteins and risk of nine cancers," are published in Nature Communications.

In these studies, the team used a powerful technique called proteomics. Proteomics allows scientists to analyze a large set of proteins in tissue samples at a single point in time, to see how they interact with each other and find any important differences in proteins between different tissue samples.

In the first study, scientists analyzed blood samples from UK Biobank that had been taken from more than 44,000 people, including over 4,900 people who subsequently had a cancer diagnosis.

Using proteomics, the team analyzed a set of 1,463 proteins from a single sample of blood from each person. They compared the proteins of people who did and did not go on to be diagnosed with cancer to look for important differences between them and find out which ones were linked to cancer risk. The scientists also identified 182 proteins that differed in the blood three years before a cancer diagnosis took place.

In the second study, the scientists looked at genetic data from over 300,000 cancer cases to do a deep dive into which blood proteins were involved in cancer development and could be targeted by new treatments.

The scientists found 40 proteins in the blood that influenced someone's risk of getting 9 different types of cancer. While altering these proteins may increase or decrease the chances of someone developing cancer, the scientists also found that in some cases this may lead to unintended side effects.

However, the team stressed that they will need to do further research to find out the exact role these proteins play in cancer development, which of the proteins are the most reliable ones to test for, which tests could be developed to detect the proteins in the clinic, and which drugs could target these proteins.

Part 1

Identifying proteomic risk factors for cancer using prospective and exome analyses of 1,463 circulating proteins and risk of 19 cancers in the UK Biobank, Nature Communications (2024). www.nature.com/articles/s41467-024-48017-6

Karl Smith-Byrne et al, Identifying therapeutic targets for cancer among 2074 circulating proteins and risk of nine cancers, Nature Communications (2024). DOI: 10.1038/s41467-024-46834-3

Part 2

Scientists generate heat over 1,000°C with solar power instead of fossil fuel

Instead of burning fossil fuels to smelt steel and cook cement, researchers in Switzerland want to use heat from the sun. The proof-of-concept study, published May 15 in the journal Device, uses synthetic quartz to trap solar energy at temperatures over 1,000°C (1,832°F), demonstrating the method's potential role in providing clean energy for carbon-intensive industries.

Glass, steel, cement, and ceramics are at the very heart of modern civilization, essential for building everything from car engines to skyscrapers. However, manufacturing these materials demands temperatures over 1,000°C and relies heavily on burning fossil fuels for heat. These industries account for about 25% of global energy consumption.

Researchers have explored a clean-energy alternative using solar receivers, which concentrate and build heat with thousands of sun-tracking mirrors. However, this technology has difficulties transferring solar energy efficiently above 1,000°C.

To boost the efficiency of solar receivers, the researchers  turned to semitransparent materials such as quartz, which can trap sunlight—a phenomenon called the thermal-trap effect. The team crafted a thermal-trapping device by attaching a synthetic quartz rod to an opaque silicon disk as an energy absorber.

When they exposed the device to an energy flux equivalent to the light coming from 136 suns, the absorber plate reached 1,050°C (1,922°F), whereas the other end of the quartz rod remained at 600°C (1,112°F).

Using a heat transfer model, the team also simulated the quartz's thermal-trapping efficiency under different conditions. The model showed that thermal trapping achieves the target temperature at lower concentrations with the same performance, or at higher thermal efficiency for equal concentration. 

Solar thermal trapping at 1000 ºC and above, Device (2024). DOI: 10.1016/j.device.2024.100399. www.cell.com/device/fulltext/S2666-9986(24)00235-7

Gut bacteria enhance cancer immunotherapy in mouse study

Roughly one in five cancer patients benefit from immunotherapy—a treatment that harnesses the immune system to fight cancer. Such an approach to beating cancer has seen significant success in lung cancer and melanoma, among others. Optimistic about its potential, researchers are exploring strategies to improve immunotherapy for cancers that don't respond well to the treatment, with the hope of benefiting more patients.

Cancer immunotherapy employs the body's immune cells to target and destroy tumors. One such treatment uses immune checkpoint inhibitor drugs to unleash the immune system by releasing the natural brakes that keep immune T cells quiet, a feature that prevents the body from harming itself. But some tumors fight back to suppress the attacking immune cells, damping the effectiveness of such inhibitors.

Now, researchers have found, in mice, that a strain of gut bacteria—Ruminococcus gnavus—can enhance the effects of cancer immunotherapy. The study, which appears May 17 in Science Immunology, suggests a new strategy of using gut microbes to help unlock immunotherapy's untapped cancer-fighting potential.

R. gnavus has been found in gut microbiota of cancer patients who respond well to immunotherapy. In clinical trials, fecal transplants from such individuals have helped some unresponsive patients reap immunotherapy's benefits.

Blanda Di Luccia et al, TREM2 deficiency reprograms intestinal macrophages and microbiota to enhance anti-PD-1 tumor immunotherapy, Science Immunology (2024). DOI: 10.1126/sciimmunol.adi5374. www.science.org/doi/10.1126/sciimmunol.adi5374

New technique to freeze brain tissue without harm

A team of medical researchers has developed a technique to freeze and thaw brain tissue without causing damage.
In their study, published in the journal Cell Reports Methods, the group tested bathing brain organoid tissue in candidate chemicals before freezing them using liquid nitrogen.

Prior research has shown that no matter how quickly brain matter is frozen, the freezing and thawing process always causes tissue damage. This has made it more difficult for researchers to study brain matter because research must be conducted immediately after obtaining a tissue sample. In this new effort, the team  found a way around this problem by soaking the tissue in a special solution before freezing.

The work involved dipping or soaking brain organoids (brain tissue grown from stem cells) in candidate compounds and then freezing and thawing them to see how they fared. After many attempts, they found one combination of solutions that worked best—a mix of ethylene glycol, methylcellulose DMSO and Y27632. They named the solution mix MEDY.

The research team then tested MEDY under a variety of conditions to see how well it prevented damage from freezing. The conditions involved changing variables, such as the age of the organoids prior to freezing and how long they were soaked in a MEDY solution. They then allowed the organoids to resume growing after they were thawed for up to 150 days.

The researchers found little difference between organoids that had been frozen and those that had not—even those that had been frozen for as long as 18 months.

As a final test, the research team used their technique on a sample of brain tissue obtained from a live human patient and found that it worked just as well.

The research team suggests that their technique should allow researchers to store brain tissue samples on a scale large enough to allow for new types of brain and nervous system research.

Weiwei Xue et al, Effective cryopreservation of human brain tissue and neural organoids, Cell Reports Methods (2024). DOI: 10.1016/j.crmeth.2024.100777

Microplastics may slow the rate at which carbon is pulled from the sea surface to the depths

Plastics in the ocean do more harm than suffocate turtles, fish and other marine life.

A new study  shows that microplastics may reduce the ability of the ocean to help offset the climate crisis by slowing down the rate at which carbon is taken from the sea surface to the depths.

For millennia, the ocean has been part of a carbon sink process in which dead phytoplankton clump together and fall into the deep ocean in showers of what look like "marine snow". The resulting carbon sequestration is a marine version of how trees and plants on terrestrial Earth take carbon from the atmosphere and store it in soil.

But new research  shows that microplastics in the ocean are slowing the process down by making the "marine snow" more buoyant. Plastics want to float. If phytoplanktons grow on microplastics in biofilms, instead of as free living organisms, that changes the buoyancy of the phytoplankton when they die.

Basically, the plastics are slowing down the sinking rate of the marine snow, which is potentially reducing the efficiency with which the ocean can remove carbon dioxide from the atmosphere.

So microplastics  could be a threat to global scale processes, such as the carbon cycle that is so important for all life.

 Kai Ziervogel et al, Microbial interactions with microplastics: Insights into the plastic carbon cycle in the ocean, Marine Chemistry (2024). DOI: 10.1016/j.marchem.2024.104395

Why digging soil is not good?

Digging disrupts natural processes that keep soil healthy and productive. Minimising cultivation is desirable when trying to grow plants in ways that have the least environmental impact.

Digging the soil bulldozes a number of structures underground. Drainage channels created by worms are destroyed, important fungal networks are broken and carbon that’s been locked in the soil is released into the atmosphere. 

Digging also brings weed seeds closer to the surface, causing them to sprout more readily.

Benefits don’t necessarily include better crops, although some gardeners have reported higher yields. 

Charles Dowding, a champion of no-dig gardening, compared side-by-side beds over eight years. One was dug, the other wasn’t. He reported 100kg of additional produce from the no-dig bed.

So how does a no-dig garden grow? Instead of cultivating the soil, no-dig gardeners cover their beds with a layer of mulch or well-rotted organic matter, either from their own compost bins or the garden centre. 

If the ground is weedy, simply cover it with a few sheets of cardboard.

Then add another layer of compost on top (this is sometimes known as lasagne gardening). 

The weeds will be smothered and plants root into the soil below, which will be enriched by the activity of worms carrying the compost into the underlying soil.

Source: 

https://www.sciencefocus.com/science/no-dig-gardening?utm_campaign=...

Discovery may explain why Egyptian pyramids were built along long-lost Ahramat branch of the Nile

Some 31 pyramids in Egypt, including the Giza pyramid complex, may originally have been built along a 64-km-long branch of the river Nile which has long since been buried beneath farmland and desert. The findings, reported in a paper in Communications Earth & Environment, could explain why these pyramids are concentrated in what is now a narrow, inhospitable desert strip.

The Egyptian pyramid fields between Giza and Lisht, built over a nearly 1,000-year period starting approximately 4,700 years ago, now sit on the edge of the inhospitable Western Desert, part of the Sahara. Sedimentary evidence suggests that the Nile used to have a much higher discharge, with the river splitting into several branches in places. Researchers have previously speculated that one of these branches may have flown by the pyramid fields, but this has not been confirmed.

Eman Ghoneim and colleagues studied satellite imagery to find the possible location of a former river branch running along the foothills of the Western Desert Plateau, very near to the pyramid fields. They then used geophysical surveys and sediment cores to confirm the presence of river sediments and former channels beneath the modern land surface, indicating the presence of a former branch, which they propose naming "Ahramat" (meaning pyramids in Arabic).

The authors suggest that an increased build-up of windblown sand, linked to a major drought which began approximately 4,200 years ago, could be one of the reasons for the branch's migration east and eventual silting up.

The discovery may explain why these pyramid fields were concentrated along this particular strip of desert near the ancient Egyptian capital of Memphis, as they would have been easily accessible via the river branch at the time they were built. Additionally, the authors found that many of the pyramids had causeways that ended at the proposed riverbanks of the Ahramat branch, which they suggest is evidence the river was used for transporting construction materials.

The findings reiterate the importance of the Nile as a highway and cultural artery for ancient Egyptians, and also highlight how human society has historically been affected by environmental change, according to the authors.

Future research to find more extinct Nile branches could help prioritize archaeological excavations along their banks and protect Egyptian cultural heritage, they add.

Eman Ghoneim, The Egyptian pyramid chain was built along the now abandoned Ahramat Nile Branch, Communications Earth & Environment (2024). DOI: 10.1038/s43247-024-01379-7. www.nature.com/articles/s43247-024-01379-7

 Quantum Breakthrough Could Charge Batteries in a Snap

Batteries based on the wave-like nature of charged particles could revolutionize energy storage, potentially cramming in more power at a faster rate than conventional electrochemical cells could ever hope to manage. A new protocol developed by a team of physicists from National Cheng Kung University could transform the basic principles of a fast-charging quantum battery into a practical system, demonstrating ways the superposition of a battery may be used to store energy quickly and efficiently.

Fundamental to quantum physics is the principle that all bits of matter have a wave-like identity that spreads out through space and time.

As counterintuitive as it is to our experience of reality, these waves represent the properties of an object – whether it's an electron, a molecule, a cat, or a whole planet – as a spectrum of possibility referred to as its superposition.

In recent years, researchers have pondered whether one or more objects in a superposition have something in common with the chaotic zip and bounce of heated material in an engine. Tapping into this quantum phenomenon could even provide new ways to transfer and hold energy.

It's a nice idea in concept, but transforming the theory behind quantum heat engines into a working device requires identifying suitable processes that don't waste a whole lot of energy.

The researchers experimentally evaluated two approaches to using the superposition of a particle to charge a hypothetical quantum battery to determine whether its fuzzy state is indeed transferring energy.

In place of an actual battery, the team simply used a trapped ion in a superposition state known as a qubit, which can gain energy as it passes through a reflective space that constrains the kinds of waves passing through.
Sending the ion through a device that split its wave into two beams, the team compared the battery's ability to store energy as separated waves passed through multiple entry points into a single cavity, and then into multiple cavities.
Not only did they find the ion's superposition really can allow for efficient charging, they found the 'many doorways, one room' approach induced an interference effect that could theoretically lead to what they call a "perfect charging phenomenon", which allows a complete conversion of stored energy to work from the quantum battery at any point in the charging process.
Part 1

They also demonstrated the process as scalable, with the interference effect persisting even when sending more than one qubit through the cavity.

By carrying out the process on the IBM Quantum Platform and IonQ's quantum hardware, the team demonstrated a proof-of-concept for their protocol, showing a similar system could have the potential to be an energy-effective way of rapidly charging and extracting power from a quantum system.
Though a qubit can simulate the fundamental physics, new methods will be needed to turn the protocol into something more practical and battery-like, meaning it will be a while before you'll be recharging your electric moped in an eyeblink.

Still, the experiment shows there's nothing in the laws of physics that says we can't exploit the quantum landscape for long-life, rapid-charging energy storage.

https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearc...

Part 2

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What is the Blood Brain Barrier?

Composition of gut microbiota could influence decision-making

The way we make decisions in a social context can be explained by psychological, social, and political factors. But what if other forces were at work? Scientists show that changes in gut microbiota can influence our sensitivity to fairness and how we treat others. Their findings are published in the journal PNAS Nexus.

The intestinal microbiota—i.e., all the bacteria, viruses and fungi that inhabit our digestive tract—plays a pivotal role in our bodies, well beyond digestive function. Recent research underscores its impact on cognition, stress, anxiety, depressive symptoms, and behaviour; mice raised in a sterile environment, for example, have difficulty interacting with other individuals.

While these findings are promising, most of this research is carried out on animals and cannot be extrapolated to humans. Nor does it allow us to understand what neuronal, immune, or hormonal mechanisms are at work in this fascinating dialogue between brain and intestine: researchers observe a link between the composition of the microbiota and social skills but do not know precisely how one controls the other.

The available data suggests that the intestinal ecosystem communicates with the central nervous system via various pathways, including the vagus nerve. It might also use biochemical signals that trigger the release of neurotransmitters, such as dopamine and serotonin, which are essential for proper brain function.

To determine whether the composition of the human gut microbiota could influence decision-making in a social setting,  researchers used behavioural tests—including the famous "ultimatum game" in which one player is given a sum of money he must split (fairly or unfairly) with a second player, who is free to decline the offer if s/he deems it insufficient. In that case, neither player receives any money.
Refusing the sum of money is equivalent to what we call "altruistic punishment," i.e., the impulse to punish others when a situation is perceived as unfair: for the second player, restoring equality (no one receives any money) sometimes feels more important than obtaining a reward. The ultimatum game is then used as an experimental way of measuring sensitivity to fairness.

To fully exploit this effect, the researchers recruited 101 participants. For seven weeks, 51 took dietary supplements containing probiotics (beneficial bacteria) and prebiotics (nutrients that promote the colonization of bacteria in the gut), while 50 others received a placebo. They all participated in an ultimatum game during two sessions at the beginning and end of the supplementation period.
Part 1

The study's results indicate that the group that received the supplements was much more inclined to reject unequal offers at the end of the seven weeks, even when the money split was slightly unbalanced. Conversely, the placebo group behaved similarly during the first and second test sessions.
Moreover, the behavioral change in the supplemented group was accompanied by biological changes: the participants who, at the start of the study, had the greatest imbalance between the two types of bacteria that dominate the gut flora (Firmicutes and Bacteroidetes) experienced the most significant change in the composition of their gut microbiota with the intake of supplements. In addition, they also showed the greatest sensitivity to fairness during the tests.
The researchers also observed a sharp drop in their levels of tyrosine, a dopamine precursor, after the seven-week intervention. For the first time, a causal mechanism is emerging: the composition of the gut microbiota could influence social behavior through the precursors of dopamine, a neurotransmitter involved in brain reward mechanisms.

"It's too early to say that gut bacteria can make us less rational and more receptive to social considerations," conclude the researchers.
However, these new results clarify which biological pathways we must look at. The prospect of modulating the gut microbiota through diet to positively influence decision-making is fascinating. We need to explore this avenue very carefully.

Marie Falkenstein et al, Impact of the gut microbiome composition on social decision-making, PNAS Nexus (2024). DOI: 10.1093/pnasnexus/pgae166

Part 2

 Rusting Rivers: The Alarming Impact of Permafrost Thaw on Arctic Rivers

In this video, researchers reveal the startling discovery of over 75 streams and rivers in Alaska's Brooks Range turning orange due to metals released in permafrost thaw. Researchers delve into the consequences of this phenomenon, its impact on aquatic ecosystems and local communities, and the ongoing research efforts to understand and mitigate these changes.

Now Cancer drug pollution is a cause for concern!

As incidence of cancer increases globally, the use of cancer drugs is also growing at a rate of approximately 10 percent per year in developed countries.
Pharmaceuticals significantly contribute to the improvement of human health; however, their environmental impacts have also become a major concern.

Cancer drugs in our ecosystems
Among the many molecules used to treat cancers are cytostatics.

As defined by the United States' National Institutes of Health (NIH), a cystostatic is "a substance that slows or stops the growth of cells, including cancer cells, without killing them."

When a cancer patient takes these drugs, the chemicals in them, including cytostatics, are eventually evacuated through the patients' solid and liquid waste.

A patients' waste ends up in the hospital or domestic wastewater system, where the chemicals in it are not entirely eliminated by end of pipe wastewater treatment plants. These chemicals can then find their way into aquatic ecosystems, and even our drinking water supply, at varying concentrations.

Cytostatic drugs are now classified as contaminants of emerging concern (CECs) due to their hazardous environmental impact.

The message is clear: this problem is only going to get worse as more people use cancer drugs.
The continuous release of pharmaceuticals into aquatic ecosystems (even at low levels) can reduce surface water quality, endanger biodiversity and disrupt ecosystem functioning.
They have a toxic impact on aquatic flora and fauna, especially the fish.

https://www.sciencedirect.com/science/article/abs/pii/S004896972205...

Scientists Confirm Microplastics Now Detected in Human Testicles

We can now add testicles to the list of places where microplastics have managed to spread – alongside human placentas, ancient rocks, clogged arteries, blue whales, baby poop, the wilderness of Antarctica, near the peak of Mount Everest, and the bottom of the ocean.

Research led by the University of New Mexico looked at testicular tissue taken from both dogs and humans, finding microplastics in every sample, with an abundance almost three times higher in humans than in dogs.
The team found an average 122.63 micrograms of microplastics per gram of tissue in canines, and 329.44 micrograms per gram in people.

Besides giving us another sobering reminder of how plastic pollution is penetrating every part of our bodies, the study raises some concerning questions in regards to how these microscopic fragments might impact male fertility.

https://academic.oup.com/toxsci/advance-article-abstract/doi/10.109...

Male and female mice exhibit different empathic behaviors to others' pain

Social interactions are multi-faceted experiences that entail understanding the emotional states of others and responding appropriately. Neuroscientists and psychologists have been studying social interactions for decades, in the hope of understanding their neural and behavioral underpinnings.

A team of researchers  recently carried out a study exploring how male and female mice respond to the pain of other mice. Their findings, published in Neuron, suggest that there are both neurobiological and behavioural differences between the two sexes, specifically in relation to their empathic responses.

Recognizing the affective states of social counterparts and responding appropriately fosters successful social interactions.

The primary objective of the recent study was to delve deeper into how male and female mammals respond to another animal in pain, both in terms of their behavior and brain activity. To do this, they carried out a series of experiments on mice, where two mice were placed in lateral chambers, while an observing mouse was placed in the central section of a common cage.

One of the mice in the lateral chamber was given an injection that caused abdominal pain, while the other two were not administered anything. The researchers monitored the behavior of the mouse in the central part of the cage, who could explore the environment freely and thus whether to interact with the other mice and in what ways.
Initially, both male and female mice moved in their surroundings, displaying similar exploratory behaviors. Yet after a while, particularly towards the end of each experimental trial, the team found that male mice exhibited more grooming behaviors, while female mice demonstrated a social preference for the mouse that was in pain, as they spent more time in its proximity and sniffing it.
"We show that male and female mice emit distinct olfactory cues after experiencing distress," the researchers wrote. "These cues activate distinct neural circuits in the piriform cortex (PiC) and evoke sexually dimorphic empathic behaviours on observers.
Specifically, the PiC → PrL pathway is activated in female observers, inducing a social preference for the distressed counterpart. Conversely, the PiC → MeA pathway is activated in male observers, evoking excessive self-grooming behaviors."
This distinct neural pathway that the researchers found to be activated in male observers originated from non-overlapping PiC neuron populations with different gene expression signatures. Notably, these gene expression signatures are regulated by transcription factors and sex hormones.
Overall, their observations suggest that male and female mice are biologically inclined to respond differently to other mice in pain. While females are more likely to get closer to a peer who is in pain, males tend to respond to another's pain with excessive self-grooming.
The results of this study could soon be explored further and validated in additional experiments. In the future, they could pave the way for the discovery of new neural processes underpinning sex-specific social behaviours.

Shunchang Fang et al, Sexually dimorphic control of affective state processing and empathic behaviors, Neuron (2024). DOI: 10.1016/j.neuron.2024.02.001

Body lice may be bigger plague spreaders than previously thought

A new laboratory study suggests that human body lice are more efficient at transmitting Yersinia pestis, the bacterium that causes plague, than previously thought, supporting the possibility that they may have contributed to past pandemics.

Y. pestis has been the culprit behind numerous pandemics, including the Black Death of the Middle Ages that killed millions of people in Europe. It naturally cycles between rodents and fleas, and fleas sometimes infect humans through bites; thus, fleas and rats are thought to be the primary drivers of plague pandemics.
Body lice—which feed on human blood—can also carry Y. pestis, but are widely considered to be too inefficient at spreading it to contribute substantially to outbreaks. However, the few studies that have addressed lice transmission efficiency have disagreed considerably.

To help clarify the potential role of body lice in plague transmission, Bland and colleagues conducted a series of laboratory experiments in which body lice fed on blood samples containing Y. pestis. These experiments involved the use of membrane feeders, which simulate warm human skin, enabling scientists to study transmission potential in a laboratory setting.

They found that the body lice became infected with Y. pestis and were capable of routinely transmitting it after feeding on blood containing levels of the pathogen similar to those found in actual human plague cases.

They also found that Y. pestis can infect a pair of salivary glands found in body lice known as the Pawlowsky glands, and lice with infected Pawlowsky glands transmitted the pathogen more consistently than lice whose infection was limited to their digestive tract. It is thought that Pawlowsky glands secrete lubricant onto the lice's mouthparts, leading the researchers to hypothesize that, in infected lice, such secretions may contaminate mouthparts with Y. pestis, which may then spread to humans when bitten. These findings suggest that body lice may be more efficient spreaders of Y. pestis than previously thought, and they could have played a role in past plague outbreaks.

 Bland DM, Long D, Rosenke R, Hinnebusch BJ (2024) Yersinia pestis can infect the Pawlowsky glands of human body lice and be transmitted by louse bite. PLoS Biology (2024). DOI: 10.1371/journal.pbio.3002625

Nightmares could be an early warning sign of an autoimmune disease flare-up – new study

Nightmares coming before autoimmune diseases have been found in other neurological diseases. Descriptions of flare-related nightmares in our study often involved being attacked, trapped, crushed or falling. Many were very distressing. One person described them as: “Horrific, like murders, like skin coming off people, horrific.” Another important finding was that these nightmares often came before a disease flare-up, particularly in people who then had hallucinations as part of their disease pattern. This was more likely in people with lupus than the other rheumatological diseases such as inflammatory arthritis. This wasn’t unexpected as lupus is known to affect the brain in some cases. Of the patients also reporting hallucinations, 61% of lupus patients and 34% with other autoimmune rheumatological diseases reported increasing disrupted sleep (mostly nightmares) just before their hallucinations.

https://theconversation.com/nightmares-could-be-an-early-warning-si...

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